[Edited 3/10/2015 @ 2:52 PM CST]
I have seen many articles regarding launcher not working. Here is several spoilers of crash reports on these forums.

1. Using drivers that dont support OpenAL

---- Minecraft Crash Report ----
// Hey, that tickles! Hehehe!

Time: 3/9/15 7:57 PM
Description: Initializing game

org.lwjgl.LWJGLException: Pixel format not accelerated
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)
at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)
at org.lwjgl.opengl.Display.createWindow(Display.java:306)
at org.lwjgl.opengl.Display.create(Display.java:848)
at org.lwjgl.opengl.Display.create(Display.java:757)
at org.lwjgl.opengl.Display.create(Display.java:739)
at avf.ap(SourceFile:534)
at avf.am(SourceFile:363)
at avf.a(SourceFile:310)
at net.minecraft.client.main.Main.main(SourceFile:124)

A detailed walkthrough of the error, its code path and all known details is as follows:
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-- Head --
Stacktrace:
at org.lwjgl.opengl.WindowsPeerInfo.nChoosePixelFormat(Native Method)
at org.lwjgl.opengl.WindowsPeerInfo.choosePixelFormat(WindowsPeerInfo.java:52)
at org.lwjgl.opengl.WindowsDisplay.createWindow(WindowsDisplay.java:247)
at org.lwjgl.opengl.Display.createWindow(Display.java:306)
at org.lwjgl.opengl.Display.create(Display.java:848)
at org.lwjgl.opengl.Display.create(Display.java:757)
at org.lwjgl.opengl.Display.create(Display.java:739)
at avf.ap(SourceFile:534)
at avf.am(SourceFile:363)

Register to memory mapping:
RAX=0x0000000000000000 is an unknown value
RBX=0x0000000000000001 is an unknown value
RCX=0x0000000000000000 is an unknown value
RDX=0x0000000000020000 is an unknown value
RSP=0x000000005c64e120 is pointing into the stack for thread: 0x000000005d00a000
RBP=0x0000000042011148 is an unknown value
RSI=0x000007fee75cfac0 is an unknown value
RDI=0x00000000004bc150 is an unknown value
R8 =0x0000000000000011 is an unknown value
R9 =0x0000000000000022 is an unknown value
R10=0x0000000000000011 is an unknown value
R11=0x0000000000000003 is an unknown value
R12=0x000000005c64e3c0 is pointing into the stack for thread: 0x000000005d00a000
R13=0x000000006907f270 is an unknown value
R14=0x000000006903c610 is an unknown value
R15=0x00000000ffffffff is an unallocated location in the heap

Your graphics card/drivers don't support OpenGL anymore. As of last year, All IntelHD 3000-4000 cards no longer support OpenGL/OpenCL games and applications.

If the computer can be modified, we recommend buying a new graphics card

buy a new computer if it is cheaper to you

6. Twitch wont load

---- Minecraft Crash Report ----
// Hey, that tickles! Hehehe!

Time: 2/19/15 3:18 PM
Description: Unexpected error

java.lang.NullPointerException: Unexpected error
at tv.twitch.ErrorCode.failed(ErrorCode.java:289)
at bqk.K(SourceFile:1338)
at bqo.g(SourceFile:186)
at avf.av(SourceFile:949)
at avf.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)

A detailed walkthrough of the error, its code path and all known details is as follows:
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